The present invention relates to modular robotic systems, and more specifically to a modular robot having independent and interchangeable modules.
Programmable robotic apparatuses are widely used to carry out a variety of tasks such as picking up, transporting and placing objects in a programmed manner. Robotic apparatuses help to reduce the amount of manual labor required to perform simple, repetitive tasks. Robotic apparatuses are widely commercially available in a variety of different configurations. The most widely used configurations are the cartesian and the scara (selective compliance assembly robot arm) configurations.
Cartesian robots have three specified directions, X, Y, and Z coordinate directions at right angles to each other. The primary advantage of cartesian robots is that these robots are capable of moving in multiple linear directions. Additionally, cartesian robots are ready to program and have a rigid structure since their axes are supported at both ends. The main disadvantage of cartesian robots is that they require a large volume of space in which to operate.
Scara robots are cylindrical robots, having two parallel rotary joints and providing compliance in one selected plane. Scara robots are generally faster than cartesian robots, however they are usually less rigid and are limited by payload. All of the joints are at the end of the arm which results in more unsupported mass and a high cantilever moment, which leads to more vibration and a loss of repeatability. What is needed is a robotic apparatus that combines the beneficial features of each of the cartesian and scara types of robots, without the limitations noted above.
Additionally, it is often desirable to be able to customize the construction of a robotic apparatus to carry out a specific task that is desired. In the prior art, often times it is necessary for one to adjust the parameters of the task to fit the specifications of a commercially available robotic apparatus, rather than being able to customize the robot to fit the desired task. Additionally, it is desirable to be able to reconfigure a robotic apparatus to allow it to perform a number of different tasks. In order to increase the versatility of robot systems, several robotic systems are known that are constructed in a modular manner. Some robotic apparatuses of the prior art are characterized by a modular design, which allows greater ease in manufacturing and installation. Examples of these types of modular robotic apparatuses include U.S. Pat. No. 5,100,286 which discloses a modular robotic apparatus that is cartesian with a rotating tooling end-effector; U.S. Pat. No. 4,766,775 which discloses a modular cylindrical robotic articulate manipulator with gripper jaw tooling; U.S. Pat. No. 4,089,427 which discloses a robotic configuration of successive modules interconnected by a connecting tube and secured by standard fastening members and which operates in cartesian or spherical coordinate systems with a point-to-point trajectory; and U.S. Pat. No. 5,523,662, which discloses an expandable configuration of successive blocks robot system with a real time controller/computer architecture.
The above prior art robotic systems support manufacturing modularity, but do not support individual module interchangeability between each axis, since the modules are fully dependent on each other and support a defined configuration and specific assembly sequence. What is needed is a modular robotic apparatus that has detachable and independent modules to provide a flexible and custom solution for different applications.
It is the object of the present invention to provide a modular robotic manipulator having individual modules that are detachable and independent in order to support interchangeability between each axis and also to provide custom design flexability.
It is a further object of the invention to provide a modular robotic manipulator that can work in both cartesian and spherical coordinate systems and can operate with a combination of rotational and translational axes of movement in a hybrid coordinate system.
The above objects have been achieved by a modular multi-axis robot that can be configured to operate with two, three, four, five or six axes of movement and in various combinations of rotational and translational motion. The modules that make up the robot are fully detachable, interchangeable and are functionally independent with respect to each adjacent module. This allows the robotic apparatus to provide a flexible solution for many different applications.
In one basic embodiment of the invention, the robot can be configured in a three axis RTT alignment including a base module having a rotational degree of freedom, an upright stand module having Z-axis degree of freedom and being mounted on the base module, a transverse gantry module mounted on the upright stand module and having a translational degree of freedom and an end effector module mounted on the gantry module for carrying out whatever manipulating function that is required of the robot. Each of the modules are electrically, mechanically and pneumatically connected to an adjacent module and this is easily facilitated by way of a quick connector coupling plate that is included on each module.
The basic embodiment, described above, can be easily expanded into a four axis RTTR (rotational-translational-translational-rotational), a five axis TRTTR, or a six axis TRTTTR robot, or can be contracted into a two-axis RT robot system depending on the desired application. Thus, the hybrid modular robotic apparatus provides a flexible solution for many different industries, such as for transferring and handling semiconductor wafers, mask and reticules, memory disks, flat panel displays, fiber optics, and other high tech components, and for operating in clean room and/or atmospheric environments.